The present invention relates to a rotor rotating device of the type employed for turning driving or driven machines.
Such a rotor rotating device serves to slowly rotate the machine shaft of turbines or compressors which are subjected to high operating temperatures. If such machines are stopped, the rotors must be prevented from bending through and no longer being balanced or contacting their stators when fully cooled. For that reason, the rotors are turned during their cooling phase, i.e. kept rotating at slow speed until they are completely cooled. The rotor rotating device also serves to overcome the breakaway moment before the subsequent turning of the rotor during the cooling phase and when they are to be started up.
In a device of this type for rotating the rotors, as disclosed in German Pat. No. 926,133, the main oil pump of the oil supply system, which in normal operation is driven directly or indirectly via a gear unit by the rotor of the driven or driving machine, can be switched from its normal operation as a driven machine to that of a driving machine which will rotate the rotor when supplied with oil under pressure. An externally driven auxiliary oil pump of the oil system then furnishes the pressurized oil to the main oil pump which is now working as a hydraulic motor.
If it is assumed that the oil supply system of a machine is very complex per se since the oil, in addition to lubricating the bearings, also serves as a control oil for the most varied regulating devices, an additional reversal of the operation of the main oil pump to that of a hydraulic motor involves a further considerable scope of technical work in the circuit arrangement of the entire oil circulation system of the machine assembly.